The goal of this research is to assess the representational validity of operational definitions of Self-disclosure (SD). Do SD questionnaires, ratings scales, coding systems and message manipulations measure what is perceived as SD by participants in the interaction? The results of this study will have important implications for theories (and research and therapy) pf psychotherapy, mental health and interpersonal relationships. The specific aim of the study is to develop a classification system of SD for observational research such that the categories of the coding scheme represent interactants' perceptions of SD. One hundred twenty subjects (60 males & 60 females) will be assigned to same-sex friend or stranger dyads. First, subjects will be complete several SD inventories. Second, they will engage in dyadic conversations that will be video-tape recorded. SD will be stimulated using a protocol to guide conversation. After the conversations subjects will make global rating of their own and their partner's SD. In a third session the video tape will be played back for the utterance by utterance basis. The video tape will also be played for two groups of naive observers. One group will use a global rating scale to rate each subject's SD for the entire conversation. The other group will rate a random sample of utterances for SD. The conversations will also be objectively coded using two coding systems and submitted to a computerized content analysis of SD. SD scores for each subject will be computed for each of the above measures and the resulting data will be analyzed using the ANOVA model with special reference to the intraclass correlation coefficient to determine the following: the extent that the measures converge on one another, whether they are specifically converging on self and recipient perceptions of SD, to what degree self and recipient perceptions of SD are similar, the relative extent that perceptions of SD are shared versus idiosyncratic, if observers' perceptions of SD are shared does the role of discloser and/or recipient modify these perceptions, does the role of friend versus stranger affect perception of SD, etc.